1. Field of the Invention
The present invention relates to a light emitting apparatus, and more particularly, to a light emitting apparatus wherein a plurality of light emitting portions are formed in a single package to implement the light with a variety of light emitting intensities and color temperatures.
2. Discussion of the Background
A light emitting diode (LED) is an element in which minority carriers (electrons or holes) are produced using a P-N junction structure of a compound semiconductor and certain light is emitted through recombination of the carriers. The light emitting diode has less electric power consumption and a longer life span of several to several ten times as compared with conventional light bulbs or fluorescent lamps, thereby having reduced electric power consumption and excellent durability. Further, the light emitting diode can be mounted in a narrow space and has strong resistance against vibration. A light emitting apparatus using such a light emitting diode has been used as a display device and a backlight. Recently, studies have been actively conducted to apply the light emitting apparatus for general illumination.
White light emitting diodes have recently appeared in addition to single color light emitting diodes, e.g., red, blue or green light emitting diodes. As a light emitting apparatus using white light emitting diodes is applied to products for vehicle and illumination, demands on the light emitting apparatus has been rapidly increased.
White light can provide various feelings depending on a light source thereof, and such a phenomenon may result from light emitting intensity or color temperature. The color temperature indicates a physical numerical value with respect to color of a light source, and is represented by Kelvin degree (K). As the color temperature rises, the light becomes blue. As the color temperature lowers, the light with strong red-yellow is emitted. In general, the activity of brain and the power of concentration increase as the color temperature rises, while the sensitivity is activated and feeling becomes comfortable as the color temperature lowers. The light emitting intensity and color temperature of such a light source may be appropriately combined to be applied to a desired use. For example, the white light with a high color temperature in a middle degree of the light emitting intensity is desirable in the daytime, in which human beings are mainly active, in order for them to concentrate on their work, and the white light with low color temperature is desirable at night, which is time for rest and sleep, in order for them to feel easy and comfortable. Further, it has been reported that the wavelength and color temperature of light sensitively operates on the growth, activity or the like of plants or animals.
However, since a conventional light emitting apparatus maintains a certain light emitting intensity and color temperature, it is cumbersome that a light emitting apparatus should be individually manufactured depending on its use. In a case where the implementation of light with different color temperatures is required as described above, a plurality of light emitting apparatuses should be manufactured and mounted to be operated. Therefore, there is a disadvantage in that a light emitting apparatus is increased in manufacturing cost and occupies a large mounting space.